Light in a Dark Room
by SineTimore
Summary: a brief follow up to Science, Interrupted. Martha and Kate share a few quiet and tender moments one the eve of Rick and Kate's engagement.


**Disclaimer:** As always, I claim ownership of nothing and offer sincerest thanks for the privilege of borrowing for a short time.

**AN:** Thank you for all of your words of support, readers. My appreciation of you is endless.

* * *

_**Light in a Dark Room**_

The unexpected sound that emanated from a nearby room didn't wake Kate. That would've meant that she'd actually been able to fall asleep, which she hadn't. Castle had drifted off hours ago, the end result of their vigorous (and extraordinarily memorable) private celebration. The soft sound of his breath soothed her as she stared blankly at the clock, and while she wanted nothing more than to follow him into the dreamland responsible for the current beauty of his slumbering face, her brain simply would not cooperate.

Their engagement was just hours old and their subsequent embarrassing encounter with Martha gone but not entirely forgotten. Caught half-dressed on the couch with her fiancé wasn't exactly how Kate had envisioned sharing her nuptial news when the time came. Martha had fun with it, though. There was that. And Castle did spend the next several hours doing his very best to make everyone and everything else in the world disappear- at which he succeeded admirably. But in the quiet aftermath, as she traced the line of the new band that encircled her finger, she couldn't stop thinking.

She rolled towards him, having decided that any attempt at sleep was futile, and brushed her lips across his bicep before delicately extricating herself from the sheet snaked around her body. His robe hung from the back of the bathroom door and she wrapped herself in it, the scent of him weaved into the cashmere from wear. Her eyes fell closed as she took it in, her mind a sudden flood of olfactory-triggered memories. When she finally made the short journey to the bedroom door, she turned back and took him in. In that moment she realized just how hard this was all going to be.

* * *

Martha stood at the kitchen counter, her back to the open room, unaware of her new company. Kate watched quietly and listened with a soft grin as the redhead grumbled in frustration at her tea bag's apparent misbehavior.

"Is everything all right, Martha?" Kate called out in hushed tone.

The brightly-robed woman turned hastily towards the origin of the voice she didn't expect. "Oh, Katherine, my word. You scared me, darling." She could feel her accelerated heartbeat pounding in her chest as she leaned back against the cold edge of the marble behind her. "What in god's name are you doing up at this hour? Oh, I hope I didn't wake you."

"No, Martha, you didn't," she insisted, pulling out a stool to sit. "I mean, I thought I heard a noise out here somewhere. It's hard to turn off the cop ears, you know? But I was awake, so…" Her voice fell off, noticeably so, and she began to fiddle with her ring again, spinning it around and around her finger.

"_Kate_?" Martha asked a second time, the first lost to the silence of the loft around them.

"I'm-I'm sorry, what?" Kate stammered, her future mother-in-law now mere inches from her position at the breakfast bar.

"Come," Martha beckoned. "Come over here and keep me company on the couch, dear girl."

She grabbed Kate's hand and spun her out of the stool, any objection futile given the insistence of her grip, and pulled them both down onto the cushions with a flourish. Even at three o'clock in the morning Martha was entirely Martha.

"Something's wrong, kiddo, I can see it all over that gorgeous face of yours. Speaking of which," she interrupted herself, "how you manage to look that gorgeous at this hour defies all logic. But, I digress," she huffed with awe and reverence. "Is it Richard? Did he do something…or _not_ do something…AGAIN?"

Kate chuckled lightly at the delivery. And at the assumption. "No, it's nothing like that. In fact- and please forgive me for what happened earlier and for not saying so then- your son made me so very happy today. Happier than I've ever been." She looked down at her left hand. "I love him so much, Martha, and I'm just-"

"Just what?" she prodded, the uncertainty in Kate's pause palpable.

"We're starting this whole new chapter together, this commitment, this engagement, and now I'm leaving in a few days and…I just want to be certain that I'm doing the right thing, you know?"

Martha smiled widely at her. In the awkwardness and brevity of their earlier exchange, there was no opportunity to talk about the job in DC or the fact that Kate had accepted it. "Good for you, kiddo. Good-for-you," she punctuated, taking Kate's hand with a squeeze. "Oh, I couldn't be more proud if you were my own daughter. They're damn lucky to have you."

"That's very sweet of you, Martha, thank you. That means a lot, really."

"Look, Kate," she began in a soft, sincere tone, "you better than most people understand just how unpredictable life can be, that anything can change from one moment to the next and that there are no guarantees. You've seen more bad than anyone ever should and you've done more good than you'll ever give yourself credit for. You're going to make a difference in a lot of people's lives down there. Everything that you've been through has led you to this very place." She brought her free hand to Kate's face to wipe away the small tear that had dropped to her cheek. "And that man in there, Kate, my son, has never loved anyone or anything as much as he loves you- with the exception of Alexis, of course. And you two will make this thing work, _together_. You got it?"

"Yeah, I got it," Kate replied with an appreciative exhale. "Thank you, Martha, for listening and for your support. It really means a lot since my mom- well, it means a lot."

"What means a lot?" Castle asked as his hand rubbed the fog from his awake-at-an-ungodly-hour eyes.

They hadn't heard him come in, which shocked them both. In that state, how he'd managed to make it from the bedroom to the couch without knocking anything over was beyond their comprehension.

"Nice hair, Castle," Kate teased, her spirit obviously lifted.

"Yes, darling, that's a good look for you. Kate's a lucky, lucky woman."

He did what he could to flatten it out but to no avail. "Okay, are we done making fun of the late guest to the pajama party?" He moved behind Kate and rested his hands on her shoulders, pulling her head back against him. "So, are we making prank phone calls and talking about boys?"

"It's scary how well you know us, Richard." Martha shook her head and got up from the couch. "Go back to bed, you two. I'm going to reheat my tea and retire, once again, to my boudoir."

Kate stood and Martha pulled her close for a hug. "Go claim everything you've earned, kiddo," she whispered before kissing her son on the cheek and making her way back to the kitchen.

Kate slid her hand down the length of Castle's arm until her hand came to rest in his. "Come on, Mr. Castle," she tugged, "let's go back to bed. That hair of yours is really only suitable for dark rooms."

"Ha, yes, very funny. Remind me when it is that you leave for DC again?"

She pushed him into the bedroom with a smile and glanced back at Martha affectionately before closing the door behind them to sleep.


End file.
